1. Field of the Invention
This invention relates to prostaglandin I2 (IP) receptor modulators, particularly IP receptor agonists, especially certain aryl carboxylic acids and aryl tetrazole derivatives, pharmaceutical compositions containing them, and methods for their use as therapeutic agents.
2. Background of the Invention
Prostacyclin (PGI2) is a member of the prostaglandin family and is the endogenous agonist ligand for the IP receptor. PGI2 exhibits numerous physiological and pharmacological effects throughout the body and has prominent actions on the cardiovascular system, especially blood vessels, various blood cells including platelets, kidneys, autonomic nerves, and components of the inflammatory and immune systems. For example, in the cardiovascular system, PGI2 produces profound vasodilatation resulting ultimately in hypotension. It also acts on non-vascular smooth muscles to cause bronchodilatation, relaxation of the uterus, and contraction of gastrointestinal smooth muscle. In addition, it decreases the pH, pepsin content, and overall secretion of gastric acid. In the blood, PGI2 inhibits the aggregation of platelets and contributes to the anti-thrombogenic properties of the intact vascular wall. The use of stable analog mimics of PGI2 also suggests that it can inhibit platelet deposition on thrombogenic surfaces such as atherosclerotic plaques. In the kidney, PGI2 provokes diuresis, natriuresis, kaliuresis, and causes secretion of renin from the renal cortex.
Due to the lability of PGI2, a variety of chemically unique analogs have been developed, but these lack receptor selectivity and/or are rapidly degraded by biotransformation. Currently, there is a need for potent, well-tolerated, highly selective IP receptor agonists with pharmacokinetics suitable for long-term, convenient (i.e., QD, BID, TID) oral dosing. The compounds of the present invention and compositions containing them address this need and are useful for the treatment of various disorders with fewer side effects.
3. Description of the Related Art
U.S. Pat. No. 3,649,637 (Howes et al.) refers to certain phenoxy tetrazole derivatives which are disclosed as being useful for treating inflammatory disorders.
U.S. Pat. No. 4,878,942 (Motegi et al.) refers to certain benzamide derivatives which are disclosed as having herbicidal and plant growth regulating activity.
U.S. Pat. Nos. 5,378,716, 5,536,736, 5,703,099, 5,935,985 (Hamaka et al.) and European Patent No. EP 558 062 B1 refer to certain phenoxyacetic acid derivatives which are disclosed as having IP receptor inhibitory activity on blood platelet aggregation.
U.S. Pat. No. 5,763,489 (Taniguchi et al.) and PCT Published Application WO 95/24393 refer to certain naphthalene derivatives which are disclosed as having IP receptor agonist activity useful for treating arterial obstruction, restenosis, arteriosclerosis, cerebrovascular disease or ischemic heart disease.
British Patent Application No. GB 1,079,414 (assigned to Smith and Nephew) refers to certain N-phenyl-o-carbamoylphenoxyacetic acid derivatives which are disclosed as having analgesic and anti-inflammatory activity.
German Patent Application No. DT 24 32 560 (assigned to Boehringer Mannheim) refers to certain 2-(4-carbaniloylalkyl)phenoxy alkanoic acid derivatives which are disclosed as being useful for treating atherosclerosis and as intermediates for antibiotics with xcex2-lactam structure.
PCT Published Application WO 99/24397 (assigned to Fujisawa) refers to certain benzocycloheptene derivatives which are disclosed as having IP receptor agonist activity useful for treating arterial obstruction, cerebrovascular disease, hepatic cirrhosis, arteriosclerosis, ischemic heart disease, restenosis after percutaneous transluminal coronary angioplasty, hypertension, and dermatosis.
PCT Published Application WO 99/32435 (assigned to Fujisawa) refers to certain naphthalene derivatives which are disclosed as having IP receptor agonist activity useful for treating arteriosclerosis, cerebrovascular disease, ischemic heart disease, dermatosis, inflammatory bowel disease, and for inhibiting cancer metastasis.
Vavayannis et al., Eur. J. Med. Chem. Chim. Ther. 1985, 20, 37-42, refers to certain dimethylcarbamate derivatives which are disclosed as being having anticholinesterase activity.
Marsh et al., J. Chem. Soc. Chem. Commun. 1996, 8, 941-942 refers to certain solid phase polyamine linkers which are disclosed as being useful in the synthesis and preparation of directed libraries against trypanothione reductase.
All publications, patents, and patent applications cited herein, whether supra or infra, are each hereby incorporated by reference in their entirety.
This invention provides compounds of Formula I: 
wherein:
R1 and R2 are each independently in each occurrence alkyl, aryl, aralkyl, heteroaryl, cycloalkyl, or heterocyclyl;
R3 and R4 are each independently in each occurrence hydrogen, alkyl, alkoxy, amino, halogen, haloalkyl, hydroxyalkyl, nitro, aryl, aralkyl, or heterocyclyl;
R5 is independently in each occurrence xe2x80x94COOR6 or tetrazolyl;
R6 is independently in each occurrence hydrogen or alkyl;
A is independently in each occurrence alkylene or alkenylene;
B is independently in each occurrence xe2x80x94O(CH2)mxe2x80x94 or xe2x80x94(CH2)nxe2x80x94;
m is independently in each occurrence an integer from 1 to 8 inclusive;
n is independently in each occurrence an integer from 0 to 8 inclusive; or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof.
This invention further relates to pharmaceutical compositions comprising a therapeutically effective amount of at least one compound of Formula I, or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof, in admixture with at least one suitable carrier. In a preferred embodiment, the pharmaceutical compositions are suitable for administration to a subject having a disease state that is alleviated by treatment with an IP receptor modulator, particularly an IP receptor agonist.
This invention further relates to pharmaceutical compositions suitable for administration to a subject comprising a therapeutically effective amount of at least one compound of Formula I, or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof, in admixture with at least one pharmaceutically acceptable carrier.
This invention further relates to methods of treatment comprising administering to a subject in need of such treatment a therapeutically effective amount of at least one compound of Formula I, or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof. In a preferred embodiment the subject in need of such treatment suffers from a disease state associated with improper wound healing, tissue necrosis, premature uterine contraction, gastric ulceration, sexual dysfunction in males and females, severe menstrual pain, improper immunoregulation, improper platelet aggregation, or improper neutrophil function. In another preferred embodiment the compound of Formula I, or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof, is an IP receptor modulator, particularly an IP receptor agonist.
This invention further relates to methods of treatment comprising administering to a subject suffering from a disease state associated with improper blood flow, a therapeutically effective amount of at least one compound of Formula I, or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof. In a preferred embodiment, the subject has a cardiovascular disease state, a hypertensive disease state, an ischemia disease state, or a renal disease state. In a more preferred embodiment, the subject has a cardiovascular disease state which is peripheral arterial occlusive disease (PAOD), intermittent claudication, critical limb ischemia, thrombotic disease, atherosclerosis, thromboangiitis obliterans (Buerger""s disease), Raynaud""s syndrome, Takayashu""s disease, migratory superficial vein thrombophlebitis, acute arterial occlusion, coronary artery disease, restenosis following angioplasty, stroke, or recurrent myocardial infarction. In another preferred embodiment, the compound of Formula I, or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof, is an IP receptor modulator, particularly an IP receptor agonist.
Definitions
Unless otherwise stated, the following terms used in this Application, including the specification and claims, have the definitions given below. It must be noted that, as used in the specification and the appended claims, the singular forms xe2x80x9ca,xe2x80x9d xe2x80x9canxe2x80x9d and xe2x80x9cthexe2x80x9d include plural referents unless the context clearly dictates otherwise.
xe2x80x9cAlkylxe2x80x9d means the monovalent branched or unbranched saturated hydrocarbon radical, consisting solely of carbon and hydrogen atoms, having from one to twelve carbon atoms inclusive, unless otherwise indicated. Examples of alkyl radicals include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, n-hexyl, octyl, dodecyl, and the like.
xe2x80x9cAlkylenexe2x80x9d means the divalent linear or branched saturated hydrocarbon radical, consisting solely of carbon and hydrogen atoms, having from one to eight carbon atoms inclusive, unless otherwise indicated. Examples of alkylene radicals include, but are not limited to, methylene, ethylene, trimethylene, propylene, tetramethylene, pentamethylene, ethylethylene, and the like.
xe2x80x9cAlkenylenexe2x80x9d means the divalent linear or branched unsaturated hydrocarbon radical, containing at least one double bond and having from two to eight carbon atoms inclusive, unless otherwise indicated. The alkenylene radical includes the cis or trans ((E) or (Z)) isomeric groups or mixtures thereof generated by the asymmetric carbons. Examples of alkenylene radicals include, but are not limited to ethenylene, 2-propenylene, 1 -propenylene, 2-butenyl, 2-pentenylene, and the like.
xe2x80x9cAlkoxyxe2x80x9d means the radical xe2x80x94OR wherein R is alkyl as defined herein. Examples of alkoxy radicals include, but are not limited to, methoxy, ethoxy, isopropoxy, butoxy, sec-butoxy, isobutoxy, and the like.
xe2x80x9cAralkylxe2x80x9d means the radical Rxe2x80x2Rxe2x80x3xe2x80x94wherein Rxe2x80x2 is an aryl radical as defined herein, and Rxe2x80x3 is an alkyl radical as defined herein. Examples of aralkyl radicals include, but are not limited to, benzyl, phenylethyl, 3-phenylpropyl, and the like.
xe2x80x9cArylxe2x80x9d means the monovalent monocyclic aromatic hydrocarbon radical consisting of one or more fused rings in which at least one ring is aromatic in nature, which can optionally be substituted with hydroxy, cyano, lower alkyl, lower alkoxy, thioalkyl, halogen, haloalkyl, hydroxyalkyl, nitro, alkoxycarbonyl, amino, alkylamino, dialkylamino, aminocarbonyl, carbonylamino, aminosulfonyl, sulfonylamino, and/or trifluoromethyl, unless otherwise indicated. Examples of aryl radicals include, but are not limited to, phenyl, naphthyl, biphenyl, indanyl, anthraquinolyl, and the like.
xe2x80x9cCycloalkylxe2x80x9d means the monovalent saturated carbocyclic radical consisting of one or more rings, which can optionally be substituted with hydroxy, cyano, alkyl, alkoxy, thioalkyl, halogen, haloalkyl, hydroxyalkyl, nitro, alkoxycarbonyl, amino, alkylamino, dialkylamino, aminocarbonyl, carbonylamino, aminosulfonyl, sulfonylamino, and/or trifluoromethyl, unless otherwise indicated. Examples of cycloalkyl radicals include, but are not limited to, cyclopropyl, cyclobutyl, 3-ethylcyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like.
xe2x80x9cHeteroarylxe2x80x9d means the monovalent aromatic carbocyclic radical having one or more rings incorporating one, two, or three heteroatoms within the ring (chosen from nitrogen, oxygen, or sulfur) which can optionally be substituted with hydroxy, cyano, lower alkyl, lower alkoxy, thioalkyl, halo, haloalkyl, hydroxyalkyl, nitro, alkoxycarbonyl, amino, alkylamino, dialkylamino, aminocarbonyl, carbonylamino, aminosulfonyl, sulfonylamino and/or trifluoromethyl, unless otherwise indicated. Examples of heteroaryl radicals include, but are not limited to, imidazolyl, oxazolyl, pyrazinyl, thiophenyl, quinolyl, benzofuryl, pyridiyl, indolyl, pyrrolyl, pyranyl, naphtyridinyl, and the like.
xe2x80x9cHeterocyclylxe2x80x9d means the monovalent saturated carbocyclic radical, consisting of one or more rings, incorporating one, two, or three heteroatoms (chosen from nitrogen, oxygen or sulfur), which can optionally be substituted with hydroxy, cyano, lower alkyl, lower alkoxy, thioalkyl, halo, haloalkyl, hydroxyalkyl, nitro, alkoxycarbonyl, amino, alkylamino, dialkylamino, aminocarbonyl, carbonylamino, aminosulfonyl, sulfonylamino and/or trifluoromethyl, unless otherwise indicated. Examples of heterocyclic radicals include, but are not limited to, morpholinyl, piperazinyl, piperidinyl, pyrrolidinyl, tetrahydropyranyl, thiomorpholinyl, and the like.
xe2x80x9cHalogenxe2x80x9d means the radical fluoro, bromo, chloro and/or iodo.
xe2x80x9cHaloalkylxe2x80x9d means alkyl as defined herein substituted in any position with one or more halogen atoms as defined herein. Examples of haloalkyl radicals include, but are not limited to, 1,2-difluoropropyl, 1,2-dichloropropyl, trifluoromethyl, 2,2,2-trifluoroethyl, 2,2,2-trichloroethyl, and the like.
xe2x80x9cHydroxyalkylxe2x80x9d means alkyl as defined herein, substituted with one or more hydroxy groups. Examples of hydroxyalkyl radicals include, but are not limited to, hydroxymethyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, 2-hydroxybutyl, 3-hydroxybutyl, 4-hydroxybutyl, 2,3-dihydroxypropyl, 1-(hydroxymethyl)-2-hydroxyethyl, 2,3-dihydroxybutyl, 3,4-dihydroxybutyl, and 2-(hydroxymethyl)-3-hydroxypropyl, and the like.
xe2x80x9cIsomerxe2x80x9d means different compounds that have the same molecular formula, but differ in the nature or the sequence of bonding of their atoms or in the arrangement of their atoms in space. Isomers that differ in the arrangement of their atoms in space are termed xe2x80x9cstereoisomersxe2x80x9d. Stereoisomers that are mirror images of each other and optically active are termed xe2x80x9cenantiomersxe2x80x9d, and stereoisomers that are not mirror images of one another are termed xe2x80x9cdiastereoisomersxe2x80x9d.
xe2x80x9cChiral isomerxe2x80x9d means a compound with one chiral center. It has two enantiomeric forms of opposite chirality and may exist either as an individual enantiomer or as a mixture of enantiomers. A mixture containing equal amounts of individual enantiomeric forms of opposite chirality is termed a xe2x80x9cracemic mixturexe2x80x9d. Compounds with more than one chiral center may exist as either an individual diastereomer or as a mixture of diastereomers, termed a xe2x80x9cdiastereomeric mixturexe2x80x9d. When one chiral center is present, a stereoisomer may be characterized by the absolute configuration (R or S) of that chiral center. Absolute configuration refers to the arrangement in space of the substituents attached to the chiral center. The substituents attached to the chiral center under consideration are ranked in accordance with the Sequence Rule of Cahn, Ingold and Prelog (Cahn et al., Angew. Chem. Inter. Edit. 1966, 5, 385; errata 511; Cahn et al., Angew. Chem. 1966, 78, 413; Cahn and Ingold J. Chem. Soc. (London) 1951, 612; Cahn et al., Experientia 1956, 12, 81; Cahn, J. Chem.Educ. 1964, 41, 116).
xe2x80x9cGeometric isomerxe2x80x9d means the diastereomers that owe their existence to hindered rotation about double bonds. These configurations are differentiated in their names by the prefixes cis- and trans-, or Zand E, which indicate that the groups are on the same or opposite side of the double bond in the molecule according to the Cahn-Ingold-Prelog rules.
xe2x80x9cAtropic isomerxe2x80x9d means the isomers owing their existence to restricted rotation caused by hindrance of rotation of large groups about a central bond.
xe2x80x9cLeaving groupxe2x80x9d means the group with the meaning conventionally associated with it in synthetic organic chemistry, i.e., an atom or group displaceable under alkylating conditions. Examples of a leaving group include, but are not limited to, halogen, alkane- or arylenesulfonyloxy, such as methanesulfonyloxy, ethanesulfonyloxy, thiomethyl, benzenesulfonyloxy, tosyloxy, and thienyloxy, dihalophosphinoyloxy, optionally substituted benzyloxy, isopropyloxy, acyloxy, and the like.
xe2x80x9cProtective groupxe2x80x9d or xe2x80x9cprotecting groupxe2x80x9d has the meaning conventionally associated with it in synthetic organic chemistry, i.e., a group which selectively blocks one reactive site in a multifunctional compound such that a chemical reaction can be carried out selectively at another unprotective reactive site. Certain processes of this invention rely upon the protecting groups to block reactive oxygen atoms present in the reactants. Acceptable protective groups for alcoholic or phenolic hydroxyl groups, which may be removed successively and selectively include groups protected as acetates, haloalkyl carbonates, benzyl ethers, alkylsilyl ethers, heterocyclyl ethers, methyl or other alkyl ethers, and the like. Protective or blocking groups for carboxyl groups are similar to those described for hydroxyl groups, preferably tert-butyl, benzyl, or methyl esters.
xe2x80x9cDeprotectionxe2x80x9d or xe2x80x9cdeprotectingxe2x80x9d is the process by which a protective group is removed after the selective reaction is completed. Certain protective groups may be preferred over others due to their convenience or relative ease of removal. Deprotecting reagents for protected hydroxyl or carboxyl groups include potassium or sodium carbonates, lithium hydroxide in alcoholic solutions, zinc in methanol, acetic acid, trifluoroacetic acid, palladium catalysts, or boron tribromide, and the like.
xe2x80x9cOptionalxe2x80x9d or xe2x80x9coptionallyxe2x80x9d means that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances in which it does not. For example, xe2x80x9coptional bondxe2x80x9d means that the bond may or may not be present, and that the description includes single, double, or triple bonds.
xe2x80x9cInert organic solventxe2x80x9d or xe2x80x9cinert solventxe2x80x9d means a solvent inert under the conditions of the reaction being described in conjunction therewith, including for example, benzene, toluene, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, chloroform, methylene chloride or dichloromethane, dichloroethane, diethyl ether, ethyl acetate, acetone, methyl ethyl ketone, methanol, ethanol, propanol, isopropanol, tert-butanol, dioxane, pyridine, and the like. Unless specified to the contrary, the solvents used in the reactions of the present invention are inert solvents.
xe2x80x9cPharmaceutically acceptablexe2x80x9d means that which is useful in preparing a pharmaceutical composition that is generally safe, non-toxic, and neither biologically nor otherwise undesirable and includes that which is acceptable for veterinary as well as human pharmaceutical use.
xe2x80x9cPharmaceutically acceptable carrierxe2x80x9d means a carrier that is useful in preparing a pharmaceutical composition that is generally compatible with the other ingredients of the composition, not deleterious to the recipient, and neither biologically nor otherwise undesirable, and includes a carrier that is acceptable for veterinary use or human pharmaceutical use. xe2x80x9cA pharmaceutically acceptable carrierxe2x80x9d as used in the specification and claims includes both one and more than one such carrier.
xe2x80x9cPharmaceutically acceptable saltxe2x80x9d of a compound means a salt that is pharmaceutically acceptable and that possesses the desired pharmacological activity of the parent compound. Such salts, for example, include:
(1) acid addition salts, formed with inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, and the like; or formed with organic acids such as acetic acid, propionic acid, hexanoic acid, cyclopentanepropionic acid, glycolic acid, pyruvic acid, lactic acid, malonic acid, succinic acid, malic acid, maleic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, 3-(4-hydroxybenzoyl)benzoic acid, cinnamic acid, mandelic acid, methanesulfonic acid, ethanesulfonic acid, 1,2-ethanedisulfonic acid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid, 2-naphthalenesulfonic acid, 4-methylbicyclo-[2.2.2]oct-2-ene-1-carboxylic acid, glucoheptonic acid, 4,4xe2x80x2-methylenebis-(3-hydroxy-2-ene-1 -carboxylic acid), 3-phenylpropionic acid, trimethylacetic acid, tertiary butylacetic acid, lauryl sulfuric acid, gluconic acid, glutamic acid, hydroxynaphthoic acid, salicylic acid, stearic acid, muconic acid, and the like;
(2) salts formed when an acidic proton present in the parent compound either is replaced by a metal ion, e.g., an alkali metal ion, an alkaline earth ion, or an aluminum ion; or coordinates with an organic base. Acceptable organic bases include ethanolamine, diethanolamine, triethanolamine, tromethamine, N-methylglucamine, and the like. Acceptable inorganic bases include aluminum hydroxide, calcium hydroxide, potassium hydroxide, sodium carbonate, sodium hydroxide, and the like.
It should be understood that a reference to a pharmaceutically acceptable salt includes the solvent addition forms or crystal forms thereof, particularly solvates or polymorphs. Solvates contain either stoichiometric or non-stoichiometric amounts of a solvent, and are often formed during the process of crystallization. Hydrates are formed when the solvent is water, or alcoholates are formed when the solvent is alcohol. Polymorphs include the different crystal packing arrangements of the same elemental composition of a compound. Polymorphs usually have different X-ray diffraction patterns, infrared spectra, melting points, density, hardness, crystal shape, optical and electrical properties, stability, and solubility. Various factors such as the recrystallization solvent, rate of crystallization, and storage temperature may cause a single crystal form to dominate.
xe2x80x9cSubjectxe2x80x9d means mammals and non-mammals. Examples of mammals include, but are not limited to, any member of the Mammalia class: humans, non-human primates such as chimpanzees and other apes and monkey species; farm animals such as cattle, horses, sheep, goats, swine; domestic animals such as rabbits, dogs and cats; laboratory animals including rodents, such as rats, mice, and guinea pigs, and the like. Examples of non-mammals include, but are not limited to birds, and the like. The term does not denote a particular age or sex.
xe2x80x9cTreatingxe2x80x9d or xe2x80x9ctreatmentxe2x80x9d of a disease state includes:
(1) preventing the disease state, i.e., causing the clinical symptoms of the disease state not to develop in a subject that may be exposed to or predisposed to the disease state, but does not yet experience or display symptoms of the disease state,
(2) inhibiting the disease state, i.e., arresting the development of the disease state or its clinical symptoms, or
(3) relieving the disease state, i.e., causing temporary or permanent regression of the disease state or its clinical symptoms.
xe2x80x9cDisease statexe2x80x9d means any disease, condition, symptom, or indication.
xe2x80x9cTherapeutically effective amountxe2x80x9d means the amount of a compound that, when administered to a subject for treating a disease state, is sufficient to effect such treatment for the disease state. The xe2x80x9ctherapeutically effective amountxe2x80x9d will vary depending on the compound, the disease state being treated, the severity of the disease state treated, the age and relative health of the subject, the route and form of administration, the judgement of the attending medical practitioner, and other factors.
xe2x80x9cModulatorxe2x80x9d means a molecule such as a compound that interacts with a target. The interactions include, but are not limited to, agonist, antagonist, and the like, as defined herein.
xe2x80x9cAgonistxe2x80x9d means a molecule such as a compound, a drug, an enzyme activator or a hormone that enhances the activity of another molecule or receptor site.
xe2x80x9cAntagonistxe2x80x9d means a molecule such as a compound, a drug, an enzyme inhibitor, or a hormone, that diminishes or prevents the action of another molecule or receptor site.
xe2x80x9cPharmacological effectxe2x80x9d encompasses effects produced in the subject that achieve the intended purpose of a therapy. In a preferred embodiment a pharmacological effect means the treatment of a subject in need of such treatment. For example, a pharmacological effect would be one that results in the prevention, alleviation or reduction of a disease state associated with improper blood flow, improper wound healing, tissue necrosis, premature uterine contraction, gastric ulceration, sexual dysfunction in males and females, alleviation of severe menstrual pain, or improper neutrophil function, in a subject in need of such treatment. In a another preferred embodiment, a pharmacological effect means that the activation of the IP receptors is associated with therapeutic benefit in a subject having a disease state treatable by the administration of an IP receptor modulator, in particular an IP receptor agonist.
Nomenclature
The naming and numbering of the compounds of this invention are illustrated below: 
In general, the nomenclature used in this Application is based on AutoNom, a Beilstein Institute computerized system for the generation of IUPAC systematic nomenclature. However, because a strict adherence to these recommendations would result in the names changing substantially when only a single substituent is changed, compounds have been named in a form that maintains consistency of nomenclature for the basic structure of the molecule.
For example, a compound of Formula I wherein R1 and R2 are each phenyl, R3 is methyl, R4 is hydrogen, R5 is xe2x80x94COOH, A is methylene, B is xe2x80x94O(CH2)mxe2x80x94, and m is 1, is named {3-[(diphenylcarbamoyloxy)methyl]-2-methylphenoxy} acetic acid.
For example, a compound of Formula I wherein R1 is phenyl, R2 is benzyl, R3 and R4 are each hydrogen, R5 is xe2x80x94COOH, A is propenylene, B is xe2x80x94(CH2)nxe2x80x94, and n is 2, is named 3-{3-[3-(benzylphenylcarbamoyloxy)propenyl]phenyl} propionic acid.
Preferred Compounds
Among the family of compounds of the present invention set forth in the Summary of the Invention, certain compounds of Formula I are preferred wherein:
R1 and R2 are each independently in each occurrence preferably aryl or aralkyl, more preferably phenyl or benzyl, most preferably phenyl.
R3 and R4 are each independently in each occurrence preferably hydrogen, alkyl, aryl, aralkyl, or halogen, more preferably hydrogen, methyl, ethyl, n-propyl, isopropyl, butyl, phenyl, benzyl, bromo, or chloro, most preferably hydrogen or methyl.
R5 is independently in each occurrence preferably xe2x80x94COOR6.
R6 is independently in each occurrence preferably hydrogen or alkyl, more preferably hydrogen.
A is independently in each occurrence preferably alkylene or alkenylene.
B is independently in each occurrence preferably xe2x80x94O(CH2)mxe2x80x94.
m is independently in each occurrence preferably an integer 1 to 5 inclusive.
n is independently in each occurrence preferably an integer 0 to 5 inclusive.
It is understood that the preferred compounds of Formula I also include the isomers of compounds of Formula I, in particular the cis and trans isomers, or racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts of solvates thereof.
Exemplary particularly preferred compounds include the following compounds of Formula I, or individual isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof: 
{3-[diphenylcarbamoyloxy)methyl]-2-methylphenoxy}acetic acid; 
[3-(3-diphenylcarbamoyloxypropyl)phenyl]acetic acid; 
cis-[3-(3-diphenylcarbamoyloxypropenyl)phenoxy]acetic acid; 
cis-3[3-(3-diphenylcarbamoyloxypropenyl)phenyl]propionic acid; 
cis-[3-(4-diphenylcarbamoyloxybut-1-enyl)phenoxy]acetic acid; 
cis-[3-(3-diphenylcarbamoyloxypropenyl)-2-methylphenoxy]acetic acid; 
cis-{3-[3-(benzylphenylcarbamoyloxypropenyl)phenoxy]acetic acid; 
trans-[3-(3-diphenylcarbamoyloxypropenyl)phenoxy}acetic acid; and 
trans-[3-(3-diphenylcarbamoyloxypropenyl)-2-methylphenoxy}acetic acid.
Compounds of this invention may be made by the methods depicted in the illustrative synthetic reaction schemes shown below.
The starting materials and reagents used in preparing these compounds are either available from commercial suppliers such as Aldrich Chemical Co., or are prepared by methods known to those skilled in the art following procedures set forth in references such as Fieser and Fieser""s Reagents for Organic Synthesis, Wiley and Sons: New York, 1991, Volumes 1-15; Rodd""s Chemistry of Carbon Compounds, Elsevier Science Publishers, 1989, Volumes 1-5 and Supplementals; and Organic Reactions, Wiley and Sons: New York, 1991, Volumes 1-40. The following schemes are merely illustrative of some methods by which the compounds of this invention can be synthesized, and various modifications to these schemes can be made and will be suggested to one skilled in the art having referred to this disclosure.
The starting materials and the intermediates of the reaction schemes may be isolated and purified if desired using conventional techniques, including but not limited to filtration, distillation, crystallization, chromatography, and the like. Such materials may be characterized using conventional means, including physical constants and spectral data.
Unless specified to the contrary, the reactions described herein take place at atmospheric pressure over a temperature range from about xe2x88x9278xc2x0 C. to about 150xc2x0 C., more preferably from about 0xc2x0 C. to about 125xc2x0 C., and most preferably and conveniently at about room (or ambient) temperature, e.g., about 20xc2x0 C.
Schemes A, B, C, and D describe alternative methods to generate the compounds of Formula I.
Scheme A describes a method of preparing a compound of Formula I wherein B is xe2x80x94O(CH2)mxe2x80x94, and R1, R2, R3, R4, R5, A and m are as defined in the Summary of the Invention. 
In general, the starting compounds of formula 1a or 1b are commercially available or are known to or can readily be synthesized by those of ordinary skill in the art. For example, synthesis of a compound 1a wherein R3 is bromo and R4 is hydrogen is described by Beijer, P. H., Rec. Trav. Chim. Pays-Bas. 1929, 48, 1010, and wherein R3 is chloro and R4 is hydrogen is described by Beuhler et al., J. Amer. Chem. Soc. 1946, 68, 574-577.
A compound of formula 1a can also be prepared by the displacement of a 2-methoxy group of 2-(2,3-dimethoxyphenyl)-4,4-dimethyl-4,5-dihydrooxazole with an alkyl group in the presence of a Grignard reagent or an organolithium reagent by methods known to one of ordinary skill in the art. Subsequent hydrolysis of the 4,5-dihydrooxazole group of compound with a strong acid such as aqueous sulfuric acid under modified of Meyers reaction condition, followed by cleavage of the 3-methoxy group to a hydroxy group with a suitable ether cleaving agent such as boron tribromide or concentrated acids such as hydrobromic acid, preferably boron tribromide gives the product compound of formula 1a. Suitable solvents for the reaction include aprotic solvents such as tetrahydrofuran, benzene, toluene, and the like. 
In step 1a, a hydroxymethyl phenol 2a is prepared by reducing the carboxylic acid group of compound 1a to an alcohol group by conventional methods. Suitable reducing conditions include lithium aluminum hydride, borane or borane derivatives in an aprotic organic solvent such as diethyl ether, dioxane, tetrahydrofuran, and the like. The compound 2a can also be prepared by cleaving the phthaloyl group of a 3-hydroxyphthalic anhydride and subsequent reduction of the product to a diol. Suitable anhydride cleaving and reducing conditions include lithium aluminum hydride, boranes or borane complexes in an aprotic organic solvent such as tetrahydrofuran, diethyl ether, dioxane, glycol ethers, and the like.
In step 2a, a hydroxymethylphenoxy carboxylic ester 4 can be prepared by alkylating the hydroxy group of compound 2a with a suitable alkylating agent 3 of the formula R5xe2x80x94(CH2)mxe2x80x94X wherein R5 is a protected carboxyl group and X is halogen, particularly bromo or chloro. The reaction proceeds in the presence of a weak base such as potassium carbonate, cesium carbonate, sodium carbonate, and the like under Williamson synthesis conditions. Suitable inert organic solvents for the reaction include aprotic organic solvents such as acetone, dioxane, tetrahydrofuran, and the like. The alkylating agents 3 are commercially available or can be synthesized by one of ordinary skill in the art.
Alternatively, in step 1b, a formylphenoxy carboxylic ester 2b is prepared by alkylating the hydroxy group of compound 1b with a suitable alkylating agent 3 of the formula R5xe2x80x94(CH2)mxe2x80x94X as described in step 2a above. Additionally, compound 2b can be synthesized by methods known to one in the art, such as by the oxidation of the primary alcohol group to the corresponding aldehyde group by suitable oxidizing agents such as dimethyl sulfoxide, acetic anhydride, oxalyl chloride, tosyl chloride, and the like. For example, synthesis of a compound of formula 2b wherein R3 is methyl, R4 is hydrogen, R5 is carboxylic acid tert-butyl ester, and m is 1, is described by Marx, M. and Tidwell, T., J. Org. Chem, 1984, 49, 788-793.
Alternatively, in step 2b, a hydroxymethylphenoxy carboxylic ester 4 can be prepared by reducing the aldehyde group of compound 2b to an alcohol group by conventional methods. Suitable aldehyde reducing conditions include reduction by lithiated hydrides such as lithium aluminum hydride, or borohydrides such as sodium borohydride, or hydrogenation using a platinum or palladium catalyst in a suitable protic solvent. Additionally, a compound of formula 4 wherein A is a branched alkylene group may be prepared treating compound 2b with an organometallic reagent such as Grignard reagent or an alkyllithium reagent. Suitable solvents for the reaction include aprotic organic solvents such as tetrahydrofuran, diethyl ether, and the like. 
In step 3, a compound of Formula I can be prepared by a various methods known to one skilled in the art. For example, the compound of Formula I can be prepared by acylating compound 4 with an acylating agent 5 of the formula R1R2NC(O)X, wherein X is halogen, particularly bromo or chloro. The reaction proceeds in the presence of a strong base such as lithium alkylamides, alkyllithiums, or potassium bis(trimethylsilyl)amide. Suitable inert organic solvents for the reaction include aprotic organic solvents such as diethyl ether, tetrahydrofuran, and the like. The acylating agents 5 are commercially available, or are known to or can readily be synthesized by those of ordinary skill in the art. For example, synthesis of the compound 5 with varying R1 and R2 can be prepared by treating the corresponding amine of the formula R1R2NH with an acyl halide such as oxalyl chloride, phosgene or phosgene equivalents, and the like.
The compound of Formula I wherein R5 is xe2x80x94COOR6 or tetrazolyl, is generally prepared as a protected group and then deprotected by conventional methods to obtain the final product. For example, the compound of Formula I wherein R5 is xe2x80x94COOR6 is prepared as a protected carboxyl group such an alkyl ester, followed by deprotection to obtain the carboxylic acid. The reaction proceeds in the presence of a strong base such as aqueous lithium hydroxide, sodium hydroxide or potassium hydroxide in a protic organic solvent such as methanol, ethanol, water, and mixtures thereof.
The compound of Formula I wherein R5 is tetrazolyl, can be prepared as a protected tetrazolyl such as the triphenylmethyl(trityl)tetrazolyl, followed by deprotection. The compound 2a can be treated with an alkylating agent of the formula Nxe2x89xa1Cxe2x80x94(CH2)mxe2x80x94X wherein X is halogen, particularly bromo or chloro. The reaction proceeds in the presence of a weak base such as potassium carbonate, cesium carbonate, or sodium carbonate, in an aprotic organic solvent such as acetone, dioxane, tetrahydrofuran, N,N-dimethylformamide, and the like. In a following step, the cyano product is reacted with an acylating agent 5 of the formula R1R2NC(O)X, wherein X is halogen, particularly bromo or chloro, and then with a sodium azide which adds to the cyano group with subsequent cyclization to form the tetrazolyl group. The reaction proceeds in the presence of a catalyst such as ammonium chloride, in an aprotic organic solvent such as acetone, dioxane, tetrahydrofuran, N,N-dimethylformamide, and the like. Alternatively, trimethylsilyl or trimethyltin azide can be used to introduce the azide group without catalysis.
Exemplary preparations of a compound of 1a are given in Preparation 1. Exemplary preparations of a compound of Formula I utilizing the reaction conditions described in Scheme A are given in Examples 1 to 5.
Scheme B describes an alternative method of preparing a compound of Formula I, particularly a trans isomer of a compound of Formula I wherein A is alkenylene, B is xe2x80x94O(CH2)mxe2x80x94, R1, R2, R3, R4, R5, and m are as defined in the Summary of the Invention. 
The alternative starting compounds, a hydroxybenzaldehyde 1b or a halogenated phenol 1c wherein X is halogen, preferably bromo or iodo, are commercially available, for example from Aldrich Chemical Company, or are known to or can readily be synthesized by those of ordinary skill in the art. 
In step 1, a trans-hydroxyphenylalkylenyl carboxylic ester 6 wherein R is (C1-C4)alkyl and Aa is a bond, alkylene or alkenylene, can be prepared by conditions known to one in the art. For example, compound 6 can be prepared by reacting the aldehyde 1b with an alkylidene-triphenylphosphorane or alkylidene phosphonate that is generated in situ by treatment of a phosphonium salt or a phosphonate such as an alkyl phosphonoacetate with a strong base such lithium hydride or sodium hydride under Wittig or Horner reaction conditions. Compound 6 can also be prepared by treating the aldehyde 1b with 1,8-diazabicyclo[5.5.0]undec-7-ene (DBU) and lithium halide under reaction conditions described by Blanchette, M. A. et al., Tetrahedron Letters, 1984, 25, 2183. Suitable solvents for the olefination reaction include inert aprotic solvents such as acetonitrile, tetrahydrofuran, and the like.
In alternative step 1, a trans-hydroxyphenylalkylenyl carboxylic ester 6 wherein R is (C1-C4)alkyl can also be prepared by reacting the halogenated phenol 1c with an acrylic ester such as ethyl acrylate in the presence of phosphine ligand such as tri-(o-tolyl)phosphine in combination with a palladium salt such as palladium(II) acetate. The reaction proceeds in the presence of a base such as triethylamine under an inert atmosphere, for example under Heck-type coupling reaction conditions. Suitable solvents for the reaction include aprotic solvents such as acetonitrile, tetrahydrofuran, and the like. 
In step 2, a trans-hydroxyphenylalkylenyl alcohol 7 is prepared by selectively reducing the carboxylic ester group of compound 6 to the corresponding alcohol group. Suitable carboxylic ester reducing conditions include lithium borohydride, lithium aluminum hydride, diisobutylaluminum hydride (DIBAL-H), borane or borane derivatives. The preferred reducing condition is described by Trost, B. M. et al., J. Org. Chem, 1980, 45, 1838, and includes the use of a salt called the ate complex formed from DIBAL-H and an alkyllithium compound such as n-butyllithium. Suitable aprotic solvents for the reaction include tetrahydrofuran, hexane, dimethoxyethane, dioxane, and the like.
In step 3, a trans-hydroxymethylalkylenyl phenoxy carboxylic ester 8 is prepared by proceeding as described in Scheme A, step 2a, for example by alkylating the hydroxy group of compound 7 with a suitable alkylating agent 3 of the formula R5xe2x80x94(CH2)mxe2x80x94X, wherein R5 is a protected carboxyl group.
In step 4, a trans isomer of a compound of Formula I is prepared by proceeding as described in Scheme A, step 3, for example, by acylating compound 8 with an acylating agent 5 of the formula R1R2NC(O)X, wherein X is halogen, particularly bromo or chloro.
Optionally, a compound of Formula I wherein A is alkylene can be prepared by selectively hydrogenating the carbon-carbon double bond of the product or any of the intermediate compounds synthesized prior to the final product, to obtain the corresponding saturated compounds. Suitable selective reducing conditions include catalytic reduction such as Raney nickel, palladium on carbon, nickel boride, platinum metal or its oxide, and the like, preferably palladium metal or its oxide. Suitable solvents for the reaction include inert organic solvents such as ethyl acetate, methanol, and the like. Preferably, compounds 6, 7, or 8 are selectively hydrogenated to obtain compounds of Formula I wherein A is alkylene.
Exemplary preparations of a trans isomer of a compound of Formula I utilizing the reaction conditions described in Scheme B are given in Examples 6 and 7. Exemplary preparations of a compound of Formula I wherein A is alkylene utilizing the reaction conditions described in Scheme B are given in Examples 11 and 12.
Scheme C describes an alternative method of preparing a compound of Formula I, particularly a cis isomer of a compound of Formula I wherein A is alkenylene, B is xe2x80x94O(CH2)mxe2x80x94, R1, R2, R3, R4, R5, and m are as defined in the Summary of the Invention. 
The starting halogenated phenol 1c wherein X is halogen, preferably bromo or iodo, is commercially available, for example from Aldrich Chemical Company, or is known to or can readily be synthesized by those of ordinary skill in the art. 
In step 1, a halophenoxy carboxylic ester 9 is prepared by proceeding as described in Scheme A, step 2a, for example by alkylating the hydroxy group of compound 1c with a suitable alkylating agent 3 of the formula R5xe2x80x94(CH2)mxe2x80x94X, wherein R5 is a protected carboxyl group.
In step 2, an hydroxymethylalkynyl phenoxy carboxylic ester 10 wherein Aa is a bond, alkylene or alkenylene, is prepared by reacting compound 9 with an alkynyl alcohol such as propargyl alcohol under acetylene coupling reaction conditions. The reaction proceeds in the presence of a organopalladium catalyst such as tetrakis(triphenylphosphine)palladium(0) or bis(triphenylphosphine)palladium(II) chloride optionally in the presence of a copper halide catalyst such as copper(I) iodide. A suitable solvent for the reaction includes pyrrolidine, which additionally serves as a reagent. Alternatively, the reaction can proceed in the presence of diisopropylamine, optionally in the presence of a copper halide catalyst, in a suitable aprotic solvent such as tetrahydrofuran.
In step 3, a alkynylphenoxy carboxylic ester 11 is prepared by proceeding as described in Scheme A, step 3, for example by acylating compound 10 with an acylating agent 5 of the formula R1R2 NC(O)X, wherein X is halogen, particularly bromo or chloro.
In step 4, a cis isomer of a compound of Formula I is prepared selectively converting the triple bond of compound 11 to a cis-double bond under partial hydrogenation conditions. Suitable catalysts for the selective partial hydrogenation of alkynes to cis-alkenes include diisobutylaluminum hydride (DIBAL) or hydrogen with a palladium catalyst such as Lindlar Catalyst. The reaction proceeds with the addition of selectivity enhancing agent such as quinoline in a protic organic solvent such as methanol.
In alternative step 3, a cis-hydroxymethylalkenyl phenoxy carboxylic ester 12 is prepared by selectively converting the triple bond of compound 10 to a cis-double bond under partial hydrogenation conditions described in step 3 above.
In alternative step 4, a cis isomer of a compound of Formula I is prepared by proceeding as described in Scheme A, step 4, for example by acylating compound 12 with an acylating agent 5 of the formula R1R2NC(O)X, wherein X is halogen, particularly bromo or chloro.
Optionally, a compound of Formula I wherein A is alkylene can be prepared by selectively hydrogenating the carbon-carbon double bond of the product or any of the intermediate compounds synthesized prior to the final product, to obtain the corresponding saturated compounds. Suitable selective reducing conditions include catalytic reduction such as Raney nickel, palladium on carbon, nickel boride, platinum metal or its oxide, and the like, preferably palladium metal or its oxide. Suitable solvents for the reaction include inert organic solvents such as ethyl acetate, methanol, and the like. Preferably, compounds 10, 11, or 12 are selectively hydrogenated to obtain compounds of Formula I wherein A is alkylene.
Exemplary preparations of the cis isomer of a compound of Formula I utilizing the reaction conditions described in Scheme C are given in Examples 8 to 10.
Scheme D describes an alternative method of preparing a compound of Formula Ia wherein A is alkenylene, B is xe2x80x94(CH2)nxe2x80x94, and R1, R2, R3, R4, R5, and n are as defined in the Summary of the Invention. 
The cis isomer of a compound of Formula Ia wherein B is xe2x80x94(CH2)nxe2x80x94 is synthesized in a manner similar to that described in Scheme C, but utilizing appropriate starting compounds to obtain desired final product.
The starting compound 1d wherein X is halogen, preferably bromo or iodo, and Z is halogen, preferably bromo or iodo, or xe2x80x94CHO or xe2x80x94(CH2)nCOOH wherein n is as defined in the Summary of the Invention, is commercially available, for example from Aldrich Chemical Company, or is known to or can readily be synthesized by those of ordinary skill in the art.
In step 1, a halophenyl carboxylic ester 13 wherein Aa is a bond, alkylene or alkenylene, can be prepared by various methods. For example, compound 13 wherein n is 3 is prepared by coupling compound 1d wherein X and Z are each halogen with a vinyl carboxylic ester such as methyl-3-butenoate in the presence of a hydroborating agent such as 9-borabicyclo[3.3.1]nonane dimer (9-BBN). The reaction proceeds in the presence of coupling catalysts such as palladium chloride and tripotassium phosphate in an aprotic solvent such as dichloromethane, N,N-dimethylformamide, tetrahydrofuran, and the like. Transesterification of the resulting carboxylic ester product is effected by treatment with an alcohol such as 2-methyl-2-propanol and a base such as n-butyllithium under an inert atmosphere.
Alternatively, the compound 13 wherein n is 2 can also be prepared by treating compound 1d wherein X is halogen and Z is xe2x80x94CHO with an alkylidene-triphenylphosphorane or alkylidene phosphonate that is generated in situ by the presence of a phosphonium salt or a phosphonate such as an alkyl phosphonoacetate with a strong base such lithium hydride or sodium hydride under Wittig or Horner reaction conditions. The resulting alkenyl carboxylic ester product is selectively hydrogenated to obtain the corresponding saturated compound. Suitable selective reducing conditions include catalytic reduction such as Raney nickel, palladium on carbon, nickel boride, platinum metal or its oxide, and the like, in an inert organic solvent such as ethyl acetate, methanol, and the like. 
In step 2, a hydroxymethylalkynylphenyl carboxylic ester 14 is prepared by proceeding as described in Scheme C, step 2, for example by treating compound 13 with an alkynyl alcohol such as propargyl alcohol. Alternatively, compound 14 wherein n is 0 or 1 can be directly prepared by reacting the starting compound 1d wherein X is halogen and Z is xe2x80x94(CH2)nCOOH wherein n is 0 or 1, respectively, with an alkynyl alcohol such as propargyl alcohol.
In steps 3 and 4, or in alternative steps 3 and 4, a compound of cis isomer of a compound of Formula Ia is then prepared by proceeding correspondingly as described in Scheme C.
Optionally, a compound of Formula Ia wherein A is alkylene and B is xe2x80x94(CH2)nxe2x80x94 can be prepared by selectively hydrogenating the carbon-carbon double bond of the product or any of the intermediate compounds synthesized prior to the final product, to obtain the corresponding saturated compounds. Suitable selective reducing conditions include catalytic reduction such as Raney nickel, palladium on carbon, nickel boride, platinum metal or its oxide, and the like, preferably palladium metal or its oxide. Suitable solvents for the reaction include inert organic solvents such as ethyl acetate, methanol, and the like. Preferably, compounds 14, 15, or 16 are selectively hydrogenated to obtain compounds of Formula Ia wherein A is alkylene.
Exemplary preparations of a compound of Formula Ia utilizing the reaction conditions described in Scheme D are given in Examples 13 to 15.
The compounds of the present invention are IP receptor modulators, in particular IP receptor agonists, and as such possess selective agonist activity at the IP receptor. These compounds (and compositions containing them) are expected to be useful in the prevention and treatment of a variety of diseases in mammals, especially humans, related directly or indirectly to blood flow disease states.
In particular, the compounds of this invention are expected to find utility in the treatment of disease states associated with cardiovascular disease states, including, but not limited to, peripheral arterial occlusive diseases (PAOD) such as intermittent claudication, critical limb ischemia, thrombotic diseases, atherosclerosis, thromboangiitis obliterans (Buerger""s disease), Raynaud""s syndrome, Takayashu""s disease, migratory superficial vein thrombophlebitis, acute arterial occlusion, coronary artery disease, restenosis following angioplasty, stroke, and recurrent myocardial infarction.
The compounds of the present invention are also useful in the treatment of hypertensive disease states including, but not limited to, general hypertension, pulmonary hypertension, occular hypertension, and tinnitus associated with hypertension.
Additionally, the compounds of the present invention are useful in treating disease states associated with ischemia including, but not limited to, ischemia associated with allograft transplantation, such as renal transplantation or other organ transplantations. The compounds of the present invention are also of use in the treatment of renal disease states including, but not limited to, renal failure, improper diuresis, improper natriuresis, and improper kaliuresis.
The compounds of the present invention may be use to treat other disease states associated with disease states including, but not limited to, improper wound healing, tissue necrosis, premature uterine contractions, gastric ulcerations, sexual dysfunction in males and females, severe menstrual pain, improper immunoregulation, improper platelet aggregation, and improper neutrophil function.
As a result of the alleviation of the blood flow disease state, the underlying pain causally related to this disease state may also be lessened or eliminated. For example, use of the compounds of the present invention may provide relief of peripheral neuropathies associated with, e.g., diabetic neuropathy, post-traumatic pain, post-surgical pain, pain associated with chemotherapy, etc.
These and other therapeutic uses are described, for example, in Goodman and Gilman""s, The Pharmacological Basis of Therapeutics, ninth edition, McGraw-Hill, New York, 1996, Chapter 26, 601-616; Coleman, R. A., Pharmacological Reviews, 1994, 46:205-229; Harrison""s Principals of Internal Medicine, fourteenth edition, McGraw-Hill, New York, 1998, 1398-1403; Handbook of Phase I/II Clinical Drug Trials, O""Grady, J. and Joubert, P. H. editors, CRC Press, New York, 1997, 249-278.
The IP receptor agonist affinity of compounds of this invention can be determined using radioligand displacement from human platelet membranes which express an endogenous IP receptor or Chinese Hamster Ovary cells expressing the recombinant rat IP receptor. The latter assay is described in more detail in Example 23.
The IP receptor agonist potency of compounds of this invention can be determined by measuring cyclic AMP accumulation in an assay utilizing either human platelets or Chinese Hamster Ovary cells expressing the recombinant rat IP receptor. The latter assay is described in more detail in Example 24.
The putative efficacy of the IP receptor agonist compounds can be identified in a canine model of peripheral vascular disease. This assay has been established as an animal model for intermittent claudication, and is described in more detail in Example 25.
The invention includes a pharmaceutical composition comprising a compound of the present invention including isomers, racemic or non-racemic mixtures of isomers, or pharmaceutically acceptable salts or solvates thereof together with one or more pharmaceutically acceptable carriers, and optionally other therapeutic and/or prophylactic ingredients.
In general, the compounds of this invention will be administered in a therapeutically effective amount by any of the accepted modes of administration for agents that serve similar utilities. Suitable dosage ranges are 1-2500 mg daily, preferably 1-1500 mg daily, and most preferably 1-500 mg daily, depending upon numerous factors such as the severity of the disease to be treated, the age and relative health of the subject, the potency of the compound used, the route and form of administration, the indication towards which the administration is directed, and the preferences and experience of the medical practitioner involved. One of ordinary skill in the art of treating such diseases will be able, without undue experimentation and in reliance upon personal knowledge and the disclosure of this application, to ascertain a therapeutically effective amount of the compounds of this invention for a given disease.
In general, compounds of this invention will be administered as pharmaceutical formulations including those suitable for oral (including buccal and sub-lingual), rectal, nasal, topical, pulmonary, vaginal or parenteral (including intramuscular, intraarterial, intrathecal, subcutaneous and intravenous) administration or in a form suitable for administration by inhalation or insufflation. The preferred manner of administration is oral using a convenient daily dosage regimen which can be adjusted according to the degree of affliction.
The compounds of the invention, together with a conventional adjuvant, carrier, or diluent, may be placed into the form of pharmaceutical compositions and unit dosages. The pharmaceutical compositions and unit dosage forms may comprise of conventional ingredients in conventional proportions, with or without additional active compounds or principles, and the unit dosage forms may contain any suitable effective amount of the active ingredient commensurate with the intended daily dosage range to be employed. The pharmaceutical composition may be employed as solids, such as tablets or filled capsules, semisolids, powders, sustained release formulations, or liquids such as solutions, suspensions, emulsions, elixirs, or filled capsules for oral use; or in the form of suppositories for rectal or vaginal administration; or in the form of sterile injectable solutions for parenteral use. Formulations containing one thousand (1000) milligrams of active ingredient or, more broadly, one hundred (100) milligrams to five hundred (500) milligrams, per tablet, are accordingly suitable representative unit dosage forms.
The compounds of the present invention may be formulated in a wide variety of oral administration dosage forms. The pharmaceutical compositions and dosage forms may comprise the compounds of the invention or its pharmaceutically acceptable salt or a crystal form thereof as the active component. The pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, pills, capsules, cachets, suppositories, and dispersible granules. A solid carrier can be one or more substances which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders, preservatives, tablet disintegrating agents, or an encapsulating material. In powders, the carrier is a finely divided solid which is a mixture with the finely divided active component. In tablets, the active component is mixed with the carrier having the necessary binding capacity in suitable proportions and compacted in the shape and size desired. The powders and tablets preferably containing from one to about seventy percent of the active compound. Suitable carriers are magnesium carbonate, magnesium stearate, talc, sugar, lactose, pectin, dextrin, starch, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose, a low melting wax, cocoa butter, and the like. The term xe2x80x9cpreparationxe2x80x9d is intended to include the formulation of the active compound with encapsulating material as carrier providing a capsule in which the active component, with or without carriers, is surrounded by a carrier, which is in association with it. Similarly, cachets and lozenges are included. Tablets, powders, capsules, pills, cachets, and lozenges can be as solid forms suitable for oral administration.
Other forms suitable for oral administration include liquid form preparations including emulsions, syrups, elixirs, aqueous solutions, aqueous suspensions, or solid form preparations which are intended to be converted shortly before use to liquid form preparations. Emulsions may be prepared in solutions in aqueous propylene glycol solutions or may contain emulsifying agents such as lecithin, sorbitan monooleate, or acacia. Aqueous solutions can be prepared by dissolving the active component in water and adding suitable colorants, flavors, stabilizing and thickening agents. Aqueous suspensions can be prepared by dispersing the finely divided active component in water with viscous material, such as natural or synthetic gums, resins, methylcellulose, sodium carboxymethylcellulose, and other well known suspending agents. Solid form preparations include solutions, suspensions, and emulsions, and may contain, in addition to the active component, colorants, flavors, stabilizers, buffers, artificial and natural sweeteners, dispersants, thickeners, solubilizing agents, and the like.
The compounds of the present invention may be formulated for parenteral administration (e.g., by injection, for example bolus injection or continuous infusion) and may be presented in unit dose form in ampoules, pre-filled syringes, small volume infusion or in multi-dose containers with an added preservative. The compositions may take such forms as suspensions, solutions, or emulsions in oily or aqueous vehicles, for example solutions in aqueous polyethylene glycol. Examples of oily or nonaqueous carriers, diluents, solvents or vehicles include propylene glycol, polyethylene glycol, vegetable oils (e.g., olive oil), and injectable organic esters (e.g., ethyl oleate), and may contain formulatory agents such as preserving, wetting, emulsifying or suspending, stabilizing and/or dispersing agents. Alternatively, the active ingredient may be in powder form, obtained by aseptic isolation of sterile solid or by lyophilisation from solution for constitution before use with a suitable vehicle, e.g., sterile, pyrogen-free water.
The compounds of the present invention may be formulated for topical administration to the epidermis as ointments, creams or lotions, or as a transdermal patch. Ointments and creams may, for example, be formulated with an aqueous or oily base with the addition of suitable thickening and/or gelling agents. Lotions may be formulated with an aqueous or oily base and will in general also containing one or more emulsifying agents, stabilizing agents, dispersing agents, suspending agents, thickening agents, or coloring agents. Formulations suitable for topical administration in the mouth include lozenges comprising active agents in a flavored base, usually sucrose and acacia or tragacanth; pastilles comprising the active ingredient in an inert base such as gelatin and glycerin or sucrose and acacia; and mouthwashes comprising the active ingredient in a suitable liquid carrier.
The compounds of the present invention may be formulated for administration as suppositories. A low melting wax, such as a mixture of fatty acid glycerides or cocoa butter is first melted and the active component is dispersed homogeneously, for example, by stirring. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool, and to solidify.
The compounds of the present invention may be formulated for vaginal administration. Pessaries, tampons, creams, gels, pastes, foams or sprays containing in addition to the active ingredient such carriers as are known in the art to be appropriate.
The compounds of the present invention may be formulated for nasal administration. The solutions or suspensions are applied directly to the nasal cavity by conventional means, for example with a dropper, pipette or spray. The formulations may be provided in a single or multidose form. In the latter case of a dropper or pipette this may be achieved by the patient administering an appropriate, predetermined volume of the solution or suspension. In the case of a spray this may be achieved for example by means of a metering atomizing spray pump.
The compounds of the present invention may be formulated for aerosol administration, particularly to the respiratory tract and including intranasal administration. The compound will generally have a small particle size for example of the order of 5 microns or less. Such a particle size may be obtained by means known in the art, for example by micronization. The active ingredient is provided in a pressurized pack with a suitable propellant such as a chlorofluorocarbon (CFC) for example dichlorodifluoromethane, trichlorofluoromethane, or dichlorotetrafluoroethane, carbon dioxide or other suitable gas. The aerosol may conveniently also contain a surfactant such as lecithin. The dose of drug may be controlled by a metered valve. Alternatively the active ingredients may be provided in a form of a dry powder, for example a powder mix of the compound in a suitable powder base such as lactose, starch, starch derivatives such as hydroxypropylmethyl cellulose and polyvinylpyrrolidine (PVP). The powder carrier will form a gel in the nasal cavity. The powder composition may be presented in unit dose form for example in capsules or cartridges of e.g., gelatin or blister packs from which the powder may be administered by means of an inhaler.
When desired, formulations can be prepared with enteric coatings adapted for sustained or controlled release administration of the active ingredient.
The pharmaceutical preparations are preferably in unit dosage forms. In such form, the preparation is subdivided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, such as packeted tablets, capsules, and powders in vials or ampoules. Also, the unit dosage form can be a capsule, tablet, cachet, or lozenge itself, or it can be the appropriate number of any of these in packaged form.
Other suitable pharmaceutical carriers and their formulations are described in Remington: The Science and Practice of Pharmacy 1995, edited by E. W. Martin, Mack Publishing Company, 19th edition, Easton, Pa. Representative pharmaceutical formulations containing a compound of the present invention are described in Examples 16 to 22.